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Finding the Fourth Proportional to 645.80, 891.18 and 351.07

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Solution

The fourth proportional to 645.80, 891.18 and 351.07 is: 484.46

Step by Step Solution

  1. Step 1: Write the proportion equation
    645.80 : 891.18 = 351.07 : x
  2. Step 2: Convert to fraction form
    645.80/891.18 = 351.07/x
  3. Step 3: Cross multiply
    645.80x = 891.18 × 351.07
  4. Step 4: Simplify right side
    645.80x = 312,864.33
  5. Step 5: Solve for x
    x = 312,864.33/645.80
  6. Step 6: Final answer
    x = 484.46

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.